| 摘要 |
PURPOSE:To reinforce a low area without degrading a sound quality by providing an electric oscillation converting means to generate acoustic oscillation and an antenna member, which is connected to the converting means and has flexibility, generating resonance to obtain a resonating frequency as a peak in the antenna member with the acoustic oscillation and oscillating whole the antenna member simultaneously. CONSTITUTION:A tube 4 to be the antenna member is fit to a lower fitting member and an upper fitting member. The tube 4 is composed of a plastic material and formed in a bellows shape. Then, it has the flexibility. An electrical signal given to a signal line 12 is converted to the acoustic oscillation in a speaker 5 and transmitted through an aperture 9a to an external part. On the other hand, this acoustic oscillation oscillates air in the tube 4 and it is propagated in the tube 4 as a pressure wave and transmitted through an aperture 8a to the external part. The surrounding frequency is also reinforced with the level of the tone of the resonating frequency, which corresponds to the length of the tube 4, as the peak, however, the peak is suppressed by the oscillation of the tube 4. Accordingly, the peak of the tone is suppressed in the resonating frequency and a smooth reinforcing characteristic without a sharp peak can be obtained. |
